This Nativity scene is made by gluing the three main pieces together. The wise men, camel and donkey can be set in front of the scene. I also like the idea of gluing colored paper behind the cutouts of the back piece. The glue up will be mounted to a small base for support.
It's very important to use contrasting woods so the manger stands out against the background. You could also use different colored stains if you like. I don't prefer stains but it could keep the cost of the project down.